Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Trade accounts receivable, allowance for doubtful accounts	$ 141	$ 181
Property, plant and equipment, accumulated depreciation	$ 8,154	$ 7,874
Capital stock, authorized shares (in shares)	3,000,000	3,000,000
Capital stock, shares issued (in shares)	0	0
Capital stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, authorized (in shares)	22,000,000	22,000,000
Common stock, shares issued (in shares)	5,792,126	5,732,505
Common stock, shares outstanding (in shares)	5,792,126	5,732,505